About session memory consume of vaadin

Hi all,
I am newbie of vaadin,I want to implements the ‘page refresh’ model in vaadin,when forward from A page(window) to B page(window),the component in page(window) A will be destroy,the session only hold the current page(window)'s component states, I think this will reduce the memory consume of session.
Is this practicable?if practicable,how to implement?